Pneumatic motor for oil-well pumps



Jan. 27, 1931 E. c. EKSTROMER PNEUMATIC MOTOR FOR OIL WELL PUMPS 7 Filed March 21 INVENTOR. 6 gm ATTORNEYS Patented Jan. 27, 1931 UNITED STATES PATENT OFFIOE EDWARD C. EKSTROMER, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, OF ONE-HALF TO JAMES F; GALLAGHER, OF BOSTON, MASSA- CHUSETTS, AND ONE-HALF TO THE EDWARD c. RENO, NEVADA, A CORPORATION or NEVADA EKSTBOMER CORPORATION, OF

PNEUMATIC MOTOR FOR OIL-WELL PUMPS Application filed March 21, 1928. Serial No. 263,412.

. My present invention relates to oil well pumping apparatus and a method of operating the same and more particularlyto an improved form of fluid pressure apparatus.

n object of my invention is to provide an improved prime mover for oil well pumps which can be lowered into the well with the pump.

Another object of my invention is to. provide an improved type of fluid pressure motor for oil well pumps and the like which can be assembled in various numbers soas to produce a power unit of any desired capacity while at the same time not enlarging the diametrical dimension to the end that, irrespecti ve of power capacity, it will always fit within the well casing. i

A further object of my invention is 'to provide a pneumatic motive power unitforoil well pumps and a method of operating the same whereby the natural gas from the Well can be utilized under pressure as the operating fluid.

Other objects and advantageous features,

some of which with the foregoing, will be set forth at length in the followingdescription oscillated by means of a pitman connected to the prime mover and a sucker rod which is attached to the walking beam and caused to move with a reciprocating movement as the walking beam is oscillated. Thesucker rod extends downwardly into the well Where it connects to the moving parts of the pump. The use of such a suckerrod is attendant with vmany undesirable features, some of which are: stretching, Whipping, and its weight. All of these undesirable features become .more exaggerated as the depth of the well increases and it is therefore desirable that some means be provided whereby these difiiculties can be overcome.

In order to overcome these difficulties, I propose to construct a prime mover element for operating a reciprocating oil well pump which can be lowered into the well and which will dispense with the use of the above-referred-to motive power means and its cooperating sucker rod. The greatest obstacle in providing such a unit is in providing a .unit small enough to be inserted into the Well casing, which casing is ofrelatively small diameter for such a purpose. This restriction in the size ofsuch a unit, however, applies only to its horizontal or diametrical dimensions and since it can be made of almost any desired length, I propose to build a fluid pressuremechanical power unit by employing a plurality of smaller power units, each of 1 which is. small'enough to be inserted in the well.' These units are then connected me-.

chanically together through a suitable piston rod which is adapted to be connected with the sucker rod of a pump which will be secured to the lower end of the motive power unit.

A further feature of my invention is the manner of operating these pneumatic mechanical power units. .It is essential that no explosive mixtures be produced Within the .well because of danger of explosions and since the use of compressed air would introduce oxygen into the well and thus form an explosive mixture, I propose to overcome this difliculty and make my device safe by utilizing the gas given off from the wells. In. the past this gas has been used for raising oil by the so-called gas lift. This method of applying the gas to this problem is very wasteful of the gas. In accordance with my invention the gas is collected in gasometers and compressed as is now commonly done where gas lifts are in operation. The gas is then stored in tanks under pressure from which it is conducted to the pneumatic power units. by means of a suitable pipe which will extend downwardly into the well alongside of the usual oil well discharge pipe.

For a better understanding of my invention, reference should be had to the accompanying drawings, in which I ha e shown by way of illustration and not of hmitation apparatus which represents the best embodiment of my device now known to me. I desire to have it understood,.however, that many changes and modifications can be made therein without departing from the'spirit of my invention.

. In these drawings:

Fig. 1 is a view in elevation showing a power unit built in accordance with my invention as it appears when lowered into the well casing,

Fig. 2 is an enlarged view in section showing51 the details of construction of my device, an

Figs. 3, 4, 5, and 6 are horizontal sectional views looking downwardly in the direction of arrows and taken respectively on the lines gI-III, IVIV; VV, and VIVI of In Fig. 1 of the drawing, 10 designates a well casing such as is commonly inserted into the well bore and 11 designates the usual oil discharge pipe through which the oil is pumped from the bottom of the well. At tached to the lower end of the discharge pipe 11, I provide a flanged coupling member 12 to which I secure fluid pressure motive power units 13 constructed in accordance with my invention, as will hereinafter appear. At the lower end of the unit or units l3,as the case may be, I attach a second flanged member 14. The flanged member 14 is provided with aconduit extending axially there- 'through and is provided with means at its lower end whereby a reciprocating pump can be "attached thereto.

In this figure of the drawing I show three motive power units connected in series, but

it should be understood that any number of such units can be used, as determined by the power or pumping capacity desired. In order to facilitate assembly of these units and provide cylinder heads therefor, I insert between adjacent units a partitioning disc 16 having suitable passageways for the oil and operating valve and piston rods therethrough. 7

By referring to Fig. 2 it will be seen that the flanged member 12 is provided with a port 17 which connects with the discharge pipe 11. This member is also provided with suitable opening and aligning ports to which pipes 18 and 19 are attached for the purpose of conducting fluid under pressure respectively to and from said motive power unit. The units 13 comprise a body member 20 having a central bore 21, within which a suitable piston 22 reciprocates. The bore 21 is provided at its ends with suitable port openings which connect with ports of an ordinary slide valve 23 for the purpose of admitting fluid under pressure into the cylinder 21 where it functions to move the piston as determined by the position of the slide valve 23. The valve 23 operates within a pressure chamber 24 formed in the body member 20 and which connects with the fluid pressure inlet pipe 18 and an exhaust port 25 is provided on the opposite side of the valve 23 which connects with the exhaust pipe 19 previously referred to. The valves 23, where a number of valves is used, are all connected to a common valve rod 26 which extends downwardly through the units and is connected at its lower end to a valve operating mechanism to be hereinafter described. Oppositely disposed from the valve chamber 25 I provide a conduit 27 which connects with the conduit 17 of the flanged member 12 through I which the oil being pumped will flow to the discharge pipe 11.

While it may be feasible to operate a pump with a single motive power unit as described above, it is believed that a greater number will be necessary in most cases; In order, therefore, to facilitate assembly of several of these units in cooperating relation, I propose to provide the discs 16 previously referred to, which discs will not only simplify the assembly of the parts but will also function as a cylinder head for the cylindrical ,bores 21. These discs 16 are provided with -suitable openings which align co-axially with the above referred to ports and chamhers so that passageways are established throughout the assembled unit. The central ope 'ng of the disc 16 provides an opening thrdiigh which a suitable piston rod-28 can operate and it is, therefore, provided with a suitable packing or stufling box so that the piston may slide freely therethrough without leakage of fluid under pressure Theattached. The member 30 is provided with an oil conduit 31 which connects with the discharge end ofthe pump 15.. The pump supporting member is also provided wlth suitable bearings 32 upon which is mounted a forked valve operating lever 33 It is also provided with a piston rod guide 34 at the lower end thereof having a suit-able packing to prevent the'escape of oil from thepump.

Below the motive power units and within the space provided, in the member 30, the piston rod is provided with suitable abutments 35 and 36, adapted to engage the forked ends of the lever 33 so as to move the valves 23 and change the direction of fluid flow therein to thus produce a reciprocating movement of the pistons 22, as will hereinafter appear in a description of the operation of my device.

Byreferring to Fig. 3 it will be seen that the flanged member 12 is so constructed that the discharge pipe 11 will be located centrally thereof to the end that, as the discharge pipe 11 is lowered into the well casing 10, the motive power units 13 will be lowered centrally of the casing without danger of jamming. This View of the drawing also shows the general arrangement of the inlet and exhaust conduits 18 and 19.

By referring to Figs. 4 and 5, it will be seen that the oil discharge conduit 27 extends substantially'half way around the cylinder 21 and provides a relatively large conduit through which the oil can flow. This conduit might be extended around the cylinder 21 a greater distance to apoint where it would meet the valve chamber 24, but in the drawing it is only shown of a cross section substantially equal to that of the discharge pipe 11. The space between the port 27 and the valve chamber 25 is shown, in these figures of the drawing, depressed to the cylinder wall for the purpose of reducing the weight of the body member 20. In Fig. 4 it will 'be seen that the exhaust chamber 25 connects with a vertical conduit 37 extending axially through the units 13 and connecting with the exhaust pipe 19. This figure of e f the drawing also shows a removable cover 38 adjacent the valve chamber which I -have provided and which can be readily removed to facilitate adjustment of the valve 23.

In Fig. 6 it will be seen that the pump supporting member 30 isv also provided with a semicircular opening which forms the conduit 31. At the lower end of this conduit the member 30 is shaped to form I acoupling means whereby the'pump can be attached to the lower end thereof with its outlet in communication with the discharge pipe 11 via the conduits 31, 27 and 17. This figure of the drawing also shows one method of mounting the valve actuating lever 33 so that its forked end is held in cooperative relation with the abutments 35 and 36 on the piston rod 28. a V 1 The operation of my invention is as follows: After the required number of units 13 has been assembled and the pump 15 attached as is illustrated in Fig. 1, the whole assembly is secured to the end of the discharge pipe 11, the inlet and exhaust pipes 18 and 19 having been previously connected, and is then lowered into the well to a point where the whole unit is submerged in oil. After the pump is properly located within the well, suit-able connections are made between the inlet pipe and a source of fluid pressure. This pressure will be transmitted through the inlet pipe to the cylinders 21 and cause the pistons 22 to operate in one direction or the other as determined by the position of the valves 23 and thereafter as the pistons reciprocate from one extreme of the stroke to the other, the abutments 35 and 36 will engage the forked lever fluid by compressing the gas at the surface ofthe well as is now commonly practiced in operating the so-called gas lift. In other respects my device will operate substantially the same as would a compressed air unit. The use of air, however, in an oil well would, as previously stated, create a hazard as it might introduce exygen into the well and thus form an explosive mixture, whereas with oil well gas there is no such danger.

-While I have shown the preferred form of my invention as now known to me, it is to be understood that Various changes may be made in its construction without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire tosecure by Letters Patent 1s 1. A fluid pressure drive for oil well pumps comprising a plurality of separable units orming an enclosing housing secured to the end of the oil discharge pipe of the well and adapted to be lowered into the well thereby, a reciprocating pump secured'to the bottom "of said housing, afluid passageway through pump.

2. A fluid pressure drive for oil well pumps comprising a plurality of separable cylinders having cooperating pistons therein, a piston rod connecting said pistons adapted to connect with and operate a pump, valves for controlling theinlet and exhaust of fluid under pressure toand from each of said cylinders, and a valve rod common to all of said valves adapted to be operated by movement of said piston rod to simultaneously operate the valves, whereby said pistons will operate in unison to drive said pump.

3. A fluid pressure driving means for oil well pumps adapted to be lowered into a well by means of attachment with the endof the oil discharge pipe comprising a body member,

a cylinder disposed axially within said body member, a piston cooperating with said cylinder to produce mechanical movement upon the admission of fluid pressure to said cylin der, a valve for controlling the admission of said fluid, a pump mounted upon the lower end of said body member adapted to be operated by movement of said piston, and a port extending through said body member connecting the discharge pipe with the pump, whereby the output of the pump will be discharged at the top of the well.

4. A pneumatic motor for oil well pumps comprising a plurality of housings adapted to be secured together end to end and lowered into the well at the end of a discharge pipe, said housings having a conduit extending therethrough communicating with said discharge pipe, a pump secured to the lower end of said housings having its outlet communieating with the conduit through said housings, cylinders and cooperating pistons arranged within said housings having a common piston rod, said pistons being connected to said pump through said piston rod, a valve for each of said cylinders, and means controlled by movement of said piston-rod adapted to simultaneously operate said valves for controlling the admission and exhaust of fluid 151N181, pressure to and fromeach of said cyliners.

5. A fluid pressure drive means for oil'well pumps comprising a plurality of separable fluid pressure motors, each having acylinder, a piston and a co-operating valve mechanism, characterized by the fact that the cylinders and valve mechanism of said motors are complementary so that any number of said mo tors may be assembled together to provide the required amount of power, the cylinders and their respective pistons and valve mechanism of each motor being all adapted to cooperate to produce a simultaneous application of power by each of said motors upon the pump in each direction of its movement. 7

EDWARD C. EKSTROMER. 

